The subject of the present invention is a device for protecting nerves after a surgical procedure.
The technical field of the invention is the manufacture of surgical equipment implantable in the human body.
One of the main applications of the invention is the manufacture of a device for protecting the median nerve and the flexor tendons of the hand, in the area of the tunnel zone of the wrist which constitutes the carpal tunnel and which is delimited by the bones of said carpal tunnel (the carpal bones) and the corresponding anterior annular ligament.
Individuals who have to perform repetitive movements of the hand may develop inflammation of the synovial tissue which surrounds the tendons, with proliferation of fibrous synovitis. The tendons are then ensheathed and the internal volume of the tunnel increases, making the fingers insensitive after a certain period of time, as a result of compression of the median nerve, and making it impossible to carry out manual work thereafter. One of the surgical solutions employed at present, and the most effective for reducing this inflammation, is to treat the carpal tunnel syndrome by surgically opening said ligament to relieve the compression on the carpal tunnel and to remove the synovial fluid which has developed there: more than 60,000 operations of this type are performed each year in France, and for each person this means at least two months off work before being able to recover complete use of the hand.
However, on account of the opening of the transverse annular ligament, whose margins are thereby cut and are left floating, the flexor tendons of the fingers may leave the carpal tunnel and the median nerve is unprotected; the patient cannot therefore start using the hand again too soon, and, despite the precautions which are taken, a recurrence rate of 5% is observed.
To remedy this disadvantage, surgeons use different methods such as partial sectioning of one of the margins of the ligament in order to move it and connect it to the other margin, at the risk of tearing this ligament, which is in fact thereby weakened.
There is not in fact at present a satisfactory response to the postoperative problems created by opening the ligament, and this is the case regardless of the tunnel zone concerned, whether the wrist, which is the most common case, or the elbow or the ankle.